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Consider the following statements regarding the axial flow in an air compressor :

1.  Surging is a local phenomenon while stalling affects the entire compressor.

2.  Stalling is a local phenomenon while surging affects the entire compressor.

3. The pressure ratio of an axial compressor stage is smaller than that of a centrifugal compressor stage.

Of these statements:

A) 1, 2 and 3 are correct

B) 1 and 2 are correct

C) 2 and 3 are correct  

D) 1 and 3 are correct.